Siren or foghorn



O. H. SVENSSON.

SIREN 0R FOGHORN.

APPLICATION FILED IIINE 30, 1921.

'l A933@ 34% v Ptented Aug. 22, 1922.

good tone.

OLOF HJALMAR SVENSSON,

Specification of i Application 1ed,)une 30,

To all whom it may concern:

Be it known that l, @Lor Hartmann SvnNssoN, a subject of the King of cSweden, siding at Gottenborg, in the county of Gottenborg` and Bohus, Sweden, have invented certain new and useful Improvements in rens or Fogliorns, of which the following is a specification.

rllhe present invention relates to sirens and particularly to suchrfog horns as used inv sailing-vessels or similar vessels lacking steam or other rvsuitable fluid for aetuatingl the siren. The present invention relates more particularly to sirens which operate by means of air, that is, compressed in a chainber by hand by means of pistons operating in cylinders, and when leaving the chamber is caused to vibrate by means of suitable devices so as to produce the tone wanted.

rEhis invention has for its object to over` come certain inconveniences in sirens or fop; horns hitherto used as made clear by Ylie following specification.

lt is of course of a particularly higl'l i1n portance, that the design of sucl'i an appliance asa foghorn be made as ren able and simple as possible, since reliability and the possibility of quick repair are oftenimportant factors in the saving of lives and valuables. A usual defect in sirens of the above mentioned kind is, that the packings of thepistons, when in operation for some time or when the siren has not been used for a long;` time, become defective. Another disadvain tage is, that the air at the )ep'inning of the compression is liable to pass by the'vibrating device without producingl any tone, and a further defect in such sirens is also the fact, that the valves between the cylinders and the compression chamber often are rather complicated and therefor expensive, such valves being` provided to enable a sufficient high air pressure for the producing of According to this invention the air discharge opening` from the compression chamber is checked by a loaded valve, which the air must lift before it can escape from the compression chamber and arrive to the vibrating device, wherethrough is attained. that the air obtains such a high compression before it leaves the compression chamber, that its pressure and speed when passing through the vibrating device produces instantly a clear and distinct tone.

This invention further consists therein,

Letters Patenti lfaitcntedfling.,

iii?

"OF GOTT'ENBORG, SWEDEN.

1921. Serial N0. 481,638.

that the bottomto which the leather pack-` ing collarofthe air-pump piston is fastened has a convex shape in relation to the said collar, whereby the leather collar is caused .to be bent, sc that a more effective packing is obtained than by a piston with a plane bottom as hitherto employed. i

This invention further consists therein, that the cylindrical inner surfaceof the partially cylindrical leather collar is provided with a split metal ring. yielding` outwardly to prevent, vthat the cylindrical portion of the :collar looses its contact withthe surface of the cylinder.

This invention finally consists therein, that the valve, which shuts off the aperture between the cylinders and the compression chamber, comprises a flap of india rubber or some similar flexible material, which by means' of a blade spring' is fastened to the fingz illustrating one embodiment of* the invention, Figure l shows a horizontallength section of the siren, Figure 2 a vertical section ofthe same on the line 1 1 in Figure 1 and Figure 3 a perspective view of a leatherr packing` collar on a larger scale.

In the embodiment shown, which has three cooperating" cylinders, 1 denotes a casing preferably of sheet-metalthe said casingv enclosing` all the operative parts of the siren. The casing 1 is by means of a partition wall 2 divided into an interior airtight space 3, within which vthe three cylinders 4; are provided, and an exterior space v5, within which a crank-shaft 6, journalled ina suitable way, operates, the said shaft having three cranks and being operable by means of a crank handle 7,l 8, outside the casing` 1. The casing 1 is provided with a cover 23 with holes 22 serving as supply openings for the air tothe cylinders 41. vThe recnprocatingpistons 9 of the lcylinders arein a known way, by means `yielding in outward direction.

the inner surfaces of the collars 12, which in a known manner are provided with a cy` lindrical operative portion, the said collars are provided each witha split metal ring 24: fitted on the inside of the cylindrical `portion of the collar 12 (see Figure 3) and The split ring 24 may be fastened to the inside ofthe collar 12 for instance by sharpening one end 25 of the same and forcing this end down into the material of the collar` 12. The o posite end 26 of vthe ring 24 is free and tliie said ring is along its circumference displaceably attached to the collar 12 by means of lugs 27 which are fastened to the said collar for instance by means of throughgoing pins 28, which of course ought'to be of a softer material than the operative surface of the cylinders 4. i

The apertures 14 between the cylinders i and the compression chamber 3 are closed by a valve, designed as a fla 15 of india rubber or any similar flexible material, which by means of a blade spring 16 is conneeted to respective cylinder el. Between the air discharge opening in the compression chamber 3 and the vibrating device 21 there is provided al box 17, which is shut ofl' from thechamber 3 by means of a valve 19 actuated upon by a spring 18 in such a way, that the air cannot escape from the chamber 3 before a pressure has been created therein which is of a sufficientv height to overcome the tension of the spring 18. Thus a suiiiciently high pressure is always guaranteed to obtain the clear tone wanted. The horn 20 with the vibrating device 21 is in any suitable manner fastenedA to the box 17.

Ifrom the foregoing I believe that the construction,'operation and advantages of the invention may be'rcadily understood by those skilled in the art, and I am awarey that various changes may be made in the details disclosed without departing .from the spirit ofthe invention as expressed in the claims.

What I want to secure by Letters Patent is: A

1. In sirens er fog horns, a cylinder, a reciprocable piston operatively mounted within said cylinder, an air chamber communicating with said cylinder so as to be supplied with compressed air by the operation ofthe piston, a passageway checked by a valve, and vibrating means communicating with said chamber through said passages way, said valve being so loaded that it is caused to open automatically for discharging the air into the vibrator, when the air iframes in said air chamber has reached a predeterminated pressure.

2. In sirens of the class mentioned, reciprocable pistons operating within cylinders, a chamber communicating with said cylinders so as to be supplied with compressed air by the operation of the pistons, vibrating means actuated upon by the compressed air, each of said pistons having a convex surface facing the pressure side of said piston, and a leather packing collar bearing against said convex surface and connected to said piston as and for the purpose set forth. i n

3. In air operated sirens, reciprocable pistons operating'within cylinders, an air 75 cylinder communicating with said cylinders so as to be supplied with compressed air by the operation of said pistons, each of said pistons being provided with a leather packing' collar, `said collar having an inner cylin- 80 vdrical surface, a split metal ring arranged within the cylindrical surface and yielding outwardly, and vibrating` means actuated by the compressed air.

4;. In sirens, reciprocating pistons operating within cylinders, an air chamber communicating with said cylinders so as to be supplied with compressed air by 'the opera tion of said pistons, leather packing collars on said pistons, each of said packing collars being provided. on its inner cylinder surface with a split yielding metal ring, said ring being fastened to the collar at one end and displaceably guided by lugs fastened to the collar, and vibrating means actuated by the vcompressed air.

5'. In sirens, a casing, a partition wall arranged within the casing and dividing` the same into two compartments, a plurality of cylinders arranged in one compartment. pistons arranged in said cylinders, means for actuating` said pistons, passageivays arranged in said cylinders and adapted to permit air compressed by said pistons to be forced in to the compartment in which the cylinders are arranged check valves controlling said air passageways7 a chamber arranged within one of said compartments and having an air passageway, a check valve for closing the air passageway leading into said chamber, a vibrating device adapted to be actuated bycompressed air within said chamber7 and a horn connected to said vibrating device. l y

In testimony whereof I have afliXc-d my signature.

OLOF vHJALMAR S VENSSON. 

